Solid state circuit components have brought incredible reduction in the size, weight and cost of audio amplifier circuitry and have also achieved increased fidelity in sound reproduction as compared with vaccuum tube technology of a prior generation. In an attempt to exploit to the limit the potential of solid state circuitry, audio engineers have striven to provide the user with increased power ratings while simultaneously achieving decreased distortion levels. Their efforts have met with resounding success, but have produced some undesirable side effects primarily in the areas of increased weight, cost and power consumption. For example, a commercially available state-of-the-art 400 watt amplifier typically weighs anywhere from 16 kilograms to over 38 kilograms depending upon the design and choice of materials. Such amplifiers normally employ costly components necessitated by the peak loads which they must carry, and generate significant amounts of heat which must be dissipated to avoid component damage.
With regard to the transformer weight problem, an obvious approach would be to reduce the number of windings and/or the gauge of the wire making up the transformer coils. However, reduction in the number of windings also reduces the inductance of the primary coil, thereby increasing idling currents through the coil and contributing to both heat generation and increased power consumption. The conventional method for achieving low idling currents in the primary has been to use a large number of windings. This approach also requires a large number of windings in the secondary to keep the voltage in the secondary at the proper level. The obvious alternative for weight reduction (i.e., reduction of the wire gauge) is not an acceptable solution since the internal resistance of each coil would be increased, leading to excessive heat generation and power loss upon high powered demands being placed on the transformer. Conventional wisdom has thus taught the necessity of increasing the size and weight of the transformer whenever a transformer powered amplifier is redesigned for increased power rating.